Mathematical basis of stability analysis =f(x,y) system of two coupled differential equations y=g(x,y) step 1 find nullclines and fixed point(s)

L14: 14 Lectures past and 1 1 to go Part 'The cell as a well-stirred bioreactor topICs Lambda phage lysis-lysogeny switch Synthetic genetic switch Switches as memory storage Chemotaxis: perfect adaptation or not? Synthetic genetic oscillators

Wrapping up E coli chemotaxis (L7& L8) Main points of last 2 lectures L7: Biological background what is the function of the individual molecules L8: modeling of all possible chemotactic reactions why doesn't this model reproduce experimentally observed perfect adaptation

Review Turing-Gierer-Meinhardt models Local excitation, global inhibition 22r+hq

Alternative views on gradient sensing Postma and van hastert. 'a diffusion-translocation model for gradient sensing by chemotactic cells Biophys.J.81,1314(2001) Levchenko and Iglesias. Models of eukaryotic gradient sensing: applications to chemotaxis of amoeba and neutrophils

一、神经管的形成 二、神经诱导作用 三、神经管的分化 四、神经元的分化 五、神经元的生长和凋亡

一、卵裂 Cleavage 二、原肠作用 Gastrulation

一、肢芽的形成 二、肢体近－远端轴线的生成 三、肢体A－P轴线的确定 四、肢体D－V轴线的确定 五、前肢和后肢发育机制有所不同 六、细胞凋亡与趾的形成 七、肢体的进化

This lecture: Mount pp 1-7, 29-35, 45-48, Next lecture: Mount pp 8-9, 65-89, 96-115, +more TheProteinDataBank(pdb-http.://ww.pdb.org/)isthesingle worldwide repository for the processing and distribution of 3-D biological macromolecular structure data Berman, H. M, J. Westbrook, Z Feng, G. Gilliland, T N. Bhat

Recursion and dynamic programming Applied dynamic programming: global alignments: Needleman-Wunsch Applied dynamic programming: local alignments Smith -Waterman Substitution matrices PAM. blosUM, Gonnet Gaps- linear and affine Alignment statistics